Why are Spellcasters not as well liked as Vampires/Werewolves?

I don’t think they’re that disliked. As others have said, the pack sold well and seems to be popular in polls. They’re definitely my favorite. I love the aesthetic of RoM and the Magic Realm. Vampires and Werewolves tend to be a darker occult by nature, being cursed predators, and all. I think the devs went with a lighter approach with RoM, which may or may not have been intentional. That might affect some folks view of the pack. Plus, the skill tree was not as complex as the other two packs.